Method for producing curved brushes



March 30, 1965 F. HERRMANN 75,8 5

METHOD FOR PRODUCING CURVED BRUSHES Filed Aug. 26, 1963 BY Mm 5,21

NVENTDR:

United States Patent M METHOD FOR PRODUCKNG CURVED BRUSHES FritzHerrrnann, Hubertusstrasse, Neuenhain, Taunus, Germany Filed Aug. 26,1963, Ser. No. 304,328

Claims priority, application Switzerland, Sept. 5, 1962,

10,534/62 7 Claims. (Cl. 300-21) This invention relates to a method forproducing curved brushes.

The production of curved brushes, especially of ringbrushes, withbristles located on the concave side, which constitutes an advantageousform for use with shoe-cleaning machines, meets with difiiculties inthat the holes required to accommodate the bristle bundles in the backof the brush have a conical form widening towards the concave side andthus can be formed by machine only from the concave side. This is,however, opposed by the curved form of the brush back, especially whenit is taken into account that the radii of curvature in ring brushesdestined for use in shoe cleaning machines are relatively small.Moulding of plastics to achieve this result encounters similardifiiculties, since the cores required to form the aforementioned holesmust be subsequently withdrawn from the finished brush backs towards theconcave side, for which insuflicient space is available.

According to the invention there is provided a method of producingcurved brushes with bristles located on the concave side, comprising,forming a plane brush back provided at least with the holes foraccommodating the bristle bundles, and causing this back to bend andtake up a predetermined curved form.

It becomes possible hereby to manufacture a split ring brush from aplane brush back with holes formed in the usual manner therein andpossibly with bristles already seated in these holes. The split can besubsequently closed by known means, for example by welding whereweldable materiais have been used. Instead of this, it is also possibleto set the split ring into a holder surrounding it, having the form of asleeve or a hoop made of metal or a plastic material and advantageouslyfastened thereto. In some cases, however, it is more advantageous toproduce, instead of a split ring, merely ring segments bycorrespondingly bending plane brush backs of requisite length, aligningthese segments, where the joints can be eliminated by the aforementionedmeans, thus in the case of weldable materials by direct welding of thesegments.

In order to reliably anchor the bristle bundle in the brush back, thelatter must have a relatively great thickness. However, the bending ofsuch a brush back meets with diificulties, owing to the great resistanceto bending and possible deformation of material. These difficulties canbe overcome by providing the brush back, before bending, on the concaveside between the holes for the bristle bundles, with cut-away portionsdesigned to reduce the resistance to bending, for example, in the formof transverse slits extending over the entire width of the back. Insteadof this, the brush back can also be provided on the concave side withhollow plugs forming sockets for the bristle bundles, whereby the backcan be kept so thin outside the hollow plugs that it can be easily bent.

It is not necessary for the bending process to bring 3,175,865 PatentedMar. 30, I965 about a permanent deformation of the brush back. Anelastic deformation or a partly elastic, partly permanent deformationcan also be brought about, if the curved form of the brush back issubsequently stabilized through bonding means or by setting the curvedback or aligned ring-brush segments into a holder.

In the accompanying drawings FIGURE 1 shows a starting material in sideelevation;

FIGURE 2 shows a side elevation of the end product; and

FIGURE 3 shows a transverse section along the line III-III in FIG. 2.

Referring to FIGURES 1 to 3, the starting product is a brush having aplane back 1. The brush back is provided on the inside, between theholes for the bristle bundles 2, with transverse slits 3 extending overthe entire width of the back. The brush back is then bent to a ringsegment with bristle bundles located on the inside. Here, the radius ofcurvature is determined by the intended radius of the ring-brush to beproduced. Further brush segments are produced in the same manner,whereafter a set of ring segments, which complete each other to form aring brush with predetermined mutual interval, are aligned and are setinto a hoop-like holder 4 (FIGS. 2 and 3). The ring segments areprovided on each end with a frontal bore 5, a helical compression spring6 being positioned in adjacent bores. The compression springs 6 areunder such a load that the segments bear against the inside of a holder4 with a predetermined force. As can be seen in FIG. 3, the holder 4 isprovided with inwardly projecting annular heads 7, which are formed byrollingin notches 8 from the outside. On the outside, the brush ringsegments are provided with corresponding annular grooves, therebysecuring the ring segments against axial displacement and forcing thering segments against the holder 4 so as to provide increased adhesionin the peripheral direction.

It is also possible to provide annular grooves on the inside of theholder and to provide the brush segments with corresponding annularribs.

What is claimed is:

1. A method for producing a ring brush for shoe cleaning machines havingbristles on the peripheral inner side thereof, comprising forming abrush back with holes for the bristle bundles inserting bristles in theholes, providing transverse slits between the holes, bending the backinto a ring segment with the bristle bundles on the inside, and mountingthe segments in a holder to form a closed ring with the ring segmentsheld together in a predetermined annular form.

2. A method according to claim 1, in which the step is included ofinserting a compression spring between each pair of adjacent ringsegments to force the segments with spring force against the holder.

3. A method according to claim 1, in which the steps are included offorming ribs in the holder and corresponding grooves in the segments tointerfit into each other.

4. A method of producing curved brushes with bristles located on theconcave side thereof including the steps of making a plurality of flatbrush backs with holes for the bristle bundles and with projections onthe opposite side of said brush backs, inserting bristles in the holes,causing the fiat back to take up the form of ring esgments, forming asleeve like annular holder with recesses in the inner side thereofcorresponding to the projections on the said brush backs and assemblingthe ring segments in the holder to form an annular brush.

5. A method as claimed in claim 4, wherein the projections on the brushback when assembled in the sleeve like solder are in the form of annularribs and the recesses in the sleeve like holder are in the form ofannular grooves.

6. A method of producing curved brushes with bristles located on theconcave side thereof including the steps of making a plurality of fiatbrush backs with holes for the bristle bundles and with recesses in theopposite side of said brush backs, inserting bristles in the holes,causing the flat back to take up the form of ring segments, forming asleeve like annular holder with projections on the inner side thereofcorresponding to the recesses in the said brush backs and assembling thering segments in the holder to form an annular brush.

7. A method as claimed in claim 6, wherein the recesses in the brushbacks when assembled in the sleeve like holder are in the form ofannular grooves and the projections on the sleeve like holder are in theform of annular ribs.

References Cited by the Examiner UNITED STATES PATENTS 1,118,156 11/14Schoede 300-21 1,663,584 3/28 Cleaves 30021 2,128,011 8/38 Morgan 15-1642,339,573 1/44 Knipp 15-201 2,616,111 11/52 Vose et a1. 30021 FOREIGNPATENTS 516,305 9/55 Canada.

GRANVILLE Y. CUSTER, JR., Primary Examiner.

1. A METHOD FOR PRODUCING A RING BRUSH FOR SHOE CLEANING MACHINES HAVINGBRISTLES ON THE PERIPHERAL INNER SIDE THEREOF, COMPRISING FORMING ABRUSH BACK WITH HOLES FOR THE BRISTLE BUNDLES INSERTING BRISTLES IN THEHOLES, PROVIDING TRANSVERSE SLITS BETWEEN THE HOLES, BENDING THE BACKINTO A RING SEGMENT WITH THE BRISTLE BUNDLES ON THE INSIDE, AND MOUNTINGTHE SEGMENTS IN A HOLDER TO FORM A CLOSED RING